The major hardware approach[2] for security or protection is the use of hierarchical protection domains. Prominent example of this approach is ring architecture with "supervisor mode" and "user mode").[3] Such approach adopts a policy already at the lower levels (hardware/firmware/kernel), restricting the rest of the system to rely on it. Therefore, the choice to distinguish between protection and security in the overall architecture design implies rejection of the hierarchical approach in favour of another one, the capability-based addressing.[1][4]